Attached is a screenshot from The National Library of Medicine. The title of the abstract, not pictured here, is "Effect of ricinoleic acid in acute and subchronic experimental models of inflammation". In short, likely as affective, or not, as capsaicin patches, i.e. Icy Hot. Not a cure, but relief. The only cure is consistent individualized physical therapy, lifestyle modification, counseling and orher therapies for stress/PTSD, diet and nutritional supplements. Doable if you're willing to work for it.

Marjean, what do you do exactly for the rub?

How do you use it and what happens with overuse?

This is new to me. May I ask what castor oil rubs are.

My DO suggested castor oil rubs for Spondylosis. It works! Just don't overdo it. I can only use 1x every 2-3 days.